Remote entanglement distribution in a quantum network via multinode indistinguishability of photons

TL;DR

This paper demonstrates a novel method for remote entanglement distribution in quantum networks by exploiting the indistinguishability of photons, eliminating the need for entangled photon sources and Bell-state measurements.

Contribution

It introduces an experimental approach that uses photon indistinguishability across multiple nodes to enable entanglement distribution without traditional swapping procedures.

Findings

Successfully distributed two-photon polarization entanglement remotely.

Showed that photon indistinguishability can replace entangled sources and Bell measurements.

Proved feasibility of multinode quantum communication using particle indistinguishability.

Abstract

Quantum networking relies on entanglement distribution between distant nodes, typically realized by swapping procedures. However, entanglement swapping is a demanding task in practice, mainly because of limited effectiveness of entangled photon sources and Bell-state measurements necessary to realize the process. Here we experimentally activate a remote distribution of two-photon polarization entanglement superseding the need for initial entangled pairs and traditional Bell-state measurements. This alternative procedure is accomplished thanks to the controlled spatial indistinguishability of four independent photons in three separated nodes of the network, which enables us to perform localized product-state measurements in the central node acting as a trigger. This experiment proves that the inherent indistinguishability of identical particles supplies new standards for feasible quantum communication in multinode photonic quantum networks.